Stock AFC spring and top end??

['956Wheel]

I have been reading posts about the 3K springs and had a couple questions:



I have the stock spring and am trying to get max mileage, If I turn the star wheel tighter does that lower top end?



Is the 3K spring softer or harder than the stock spring?



I am "playing" with the AFC housing position as well as the Star wheel trying to get max MPG while maintaining "driveabiliy". What exactly does the AFC position do?



TIA



Mike

 

[Deezul1]

The GSK spring kit is a different thing than the AFC spring. The Governor spring kit goes down inside the pump replacing the stock springs and seats to allow you to rev higher without defueling depending on which kit you buy the 3000rpm kit or the 4000 rpm kit. The AFC spring is what allows fueling in relation to boost pressure and the adjustment determines if you fuel at low boost or wait till higher boost, low boost fueling usually means more smoke but better power at slow speeds.

 

['956Wheel]

DEEZUL,



There must be a good book that covers the P7100, I have the DC book as well as a Cummins book and neither seem to cover the pump in detail..... but then I guess we ain't supposed to be messing with it!



Mike

 

[Deezul1]

Try this place





http://www.sae.org/servlets/productDetail?PROD_TYP=BOOK&PROD_CD=BOSCHTECH-16